Initial Incident Report: Multiple scan emails or SMS alerts
Early this morning we experienced a problem which resulted in both paid and free Gravityscan customers receiving multiple alerts via SMS or email. All but one of the alerts would have said:
“We encountered a problem scanning your site [yoursite], and were unable to continue: Due to multiple scans running against this site, your scan has been aborted to avoid overwhelming the server.”
This was caused by a problem in our scheduled scan system. We usually have a single process per website being scanned, and in this case we had multiple processes pick up scan jobs for websites and attempt to scan those sites.
We have a safety mechanism built into Gravityscan that prevents too many scans from occurring on a single site, across all our scanners. This is to avoid overwhelming any single site with traffic. It acts as a safety mechanism internally and also prevents someone malicious from abusing Gravityscan to perform a denial-of-service attack on a website.
This mechanism kicked in and aborted the additional scans. The results were that our customers, both free and paid, received alerts saying that one scan had succeeded, but then additional alerts were received with the above message saying that your scan had been aborted.
The Gravityscan team caught this immediately and responded very quickly. They have already performed an initial analysis and fixed the underlying issue. We are working through a root cause analysis.
Our apologies for any inconvenience this caused. I will post any additional pertinent updates that may result from our root cause analysis.
Mark Maunder – Wordfence & Gravityscan founder & CEO.